The 29-year-old is now attracting interest from the Hammers and the Saints, and he could pretty much be guaranteed a spot on the right side of the attack, given the pair have struggled to score goals on a regular basis this campaign.
The 28-year-old has fallen out of favour in north London and is now free to leave Arsenal, providing a suitable offer comes in.
Arsene Wenger has rarely called upon the 28-year-old this season, fielding him three times as a substitute in the Premier League with his other six appearances coming in the Europa League and Carabao Cup.
A number of players are expected to leave the Emirates between now and the start of next season, with the contracts of Mesut Ozil, Alexis Sanchez and Jack Wilshere all expiring at the end of the current campaign.
The Frenchman eventually penned a two-year extension to remain in north London but negotiations over Ozil's contract have not yet resumed and the 2014 World Cup victor could follow Sanchez's example and walk away for nothing at the end of the season.
With both Alexis Sanchez and Mesut Ozil reluctant to extend their contracts beyond next summer, Wenger is looking to recoup as much as possible from his fringe players, and Walcott is seemingly leading the exit list with the transfer window reopening in just over 25 days' time. Signed from Southampton for £12m as a 16-year-old, Walcott arrived with the tag of being arguably one of English football's brightest talents but a series of injuries and indifferent performances hampered his development.